COLEOPTERA. 75 
orbicular. The elytra are frequently somewhat inclined laterally, or 
tectiform, flattened, and rounded. These Insects simulate death when 
they are seized, and several, thus situated, produce a caustic yellowish 
liquid of a penetrating odour, from the articulations of their feet; 
the organs which secrete it have not yet been detected. 
Various species—Meloes, Mylabres, Cantharides—are employed 
externally as epispastics, and internally as a powerful stimulant; the 
latter use of them, however, is extremely dangerous. 
This tribe is formed of the genus 
Me oe, Lin., 
Which has been divided into several others. The anatomical ob- 
servations of M. Leon Dufour, with the highly interesting experi- 
ments of Dr. Bretonneau, of Tours, on the vesicating property of the 
Insects of this tribe, and of several other Coleoptera, enable us to 
arrange these generic sections in a natural order, which differs but 
little from that we have already adopted. The latter gentleman has 
ascertained that the Sitares do not possess the property in question, 
and the former found but four biliary vessels in the same Heteromera, 
instead of six, which exist in the other Insects of this tribe. Indepen- 
dently of this, Sitaris resembles Zonitis in the whole ensemble of the 
organization, and these latter are contiguous to the Cantharides. 
These Insects thus occupying one of the extremities of this tribe, it 
is easy, by a comparative study of their other relations, to follow the 
series until we reach the opposite extremity—it accords with the 
progressive changes in the form of the antenne. 
In some, those of both sexes consist of but nine joints, the last of 
which is very large, and in the form of an ovoid head *; those of the 
males, as well as their maxillary palpi, are very irregular. The body 
is depressed. Such is the 
Crrocoma, Geoff. Scheff. Fab. 
These Insects make their appearance during the summer solstice, 
and frequently in great numbers in the same spot; they are found on 
flowers, particularly on those of the wild Chamomile, the Milfoil &c. 
C. Sche fferi ; Meloe Sche ffert, L.; Oliv., Col,, III, 48, i, 1. 
Green or bluish-green ; antennze and feet of a wax-yellow ft. 
Jn al] the others, the palpi are identical and irregular in both sexes. 
The antenne usually consist of eleven joints, and when there is one 
or two less, they always terminate regularly inaclub. The body is 
tolerably thick, and the elytra are somewhat inclined. 
In these, the antennze, always regular and granose in both sexes, 
sometimes appearing to be composed of nine or ten joints t, and 
* All the Insects of this tribe with clavate antenne, or such as are larger near 
the end, are foreign to New Holland and America. 
+ See Lat., Gener. Crust. et Insect., II, p. 212; Olivier, Fabricius, Schcenherr, 
and Fischer, Entomog. Imp. Ross., JI, xli, 1, 2, 3. 4. 
+t The two or three last ones appear to be confounded or intimately united, at 
least in the females; for the articulations of the clatibe more distinct in th 
males. 
G2 
